Gone with the wind: dune provenance and sediment recycling in the northern Rub’ al-Khali, United Arab Emirates

The Rub’al-Khali dune field in southern Arabia is the largest sand sea in the world. Deciphering thepalaeoenvironmental history of the Rub’al-Khali is critical to understanding its role as a barrier to human migration, dispersaland settlement. To determine sediment provenance and transport pathways, we combined data from a geological mappingproject with traditional heavy mineral optical point-counting methods, heavy mineral geochemical fingerprinting and detritalzircon U–Pb geochronology of Miocene and Quaternary sediments in the United Arab Emirates (UAE). Detrital zircon U–Pbage spectra demonstrate that most Neogene and Quaternary sediments in the UAE are ultimately sourced from the PrecambrianArabian Shield. Heavy mineral and geochemical signatures indicate that the dune sands are locally recycled from the deflationof Miocene sandstones and Quaternary siliciclastic palaeodunes exposed along the Arabian Gulf coast, whereas carbonatepalaeodunes along the Gulf coast are derived from the deflation of sediments deposited by the Tigris–Euphrates River system inthe Gulf during Pleistocene lowstands. In the eastern Emirates, Miocene and Quaternary alluvial fan deposits emanating fromthe Hajar Mountains have an ophiolitic heavy mineral signature. The data reveal new insights into the origin and developmentof the Rub’al-Khali dune field.